Throughout this application, various references are referred to. Disclosures of these publications in their entireties are hereby incorporated by reference into this application to more fully describe the state of the art to which this invention pertains.
This invention relates to an apparatus for preparing a beverage fit for consumption, such as coffee, tea, chocolate and cappuccino. The sealing locking mechanism used by most existing beverage machines, seal the coffee chamber by mechanical means only. For example, in current beverage machines, coffee is placed on a stainless steel or aluminum filter cup which consists of three bayonet type fittings. The brew head's side has a counter recess which fits to the cup. The user turns a handle on the filter cup to lock in the bayonet fitting to the brew head. A silicone seal ring is fixed on the brew head. Once the filter cup is locked into the brew head, the seal ring seals the top edge of the filter cup to prevent water leaking from it. Another example of this apparatus is the single serve pod coffee machine. In this design, the locking mechanism is a slider or turning ring which locks on the brew chamber bottom. The slider or turning ring has tabs and corresponding recesses on the support base. This seal ring, which has minor expanding capability, is fixed on the brew head. Both locking mechanisms described use a mechanical method to seal the filter cup/pod holder to the seal ring.
The drawback of this design is that the silicone sealing ring has very limited expanding capability. As such, when the pump pressure increases greater than the sealing force, the brew head and seal ring rise, but the filter cup and pod holder do not. As a result leaking results from the gap formed between the seal ring and the filter cup/pod holder.
The claimed invention solves this problem because sealing occurs by hydraulic means and not by mechanical locking. The claimed invention uses an expandable seal mounted on the boiler. When water is pumped to the boiler, the piston seal expands sealing the piston to the pod holder. The greater the pressure created by the pump, the greater the back pressure exerted against the pod and, in consequence, stronger is seal between the piston and pod holder.
The foregoing objects and advantages of the present invention are illustrative of those that can be achieved by the present invention and are not intended to be exhaustive or limiting of the possible advantages which can be realized. Thus these and other objects and advantages of the invention will be apparent from the description herein or can be learned from practicing the invention, both as embodied herein or as modified in view of any variation which may be apparent to those skilled in the art. Accordingly, the present invention resides in the novel methods, arrangements, combinations and improvements herein shown and described.